Preparation And Properties Of Conductive Nanocomposites

Conductive polymer nanocomposites have attracted wide attention because of their good processability,low-cost,adjustable electrical properties and wide applications.The satisfactory conductive polymer nanocomposites can be obtained by combining conductive fillers with insulating polymer matrix via using suitable processing technology.Conductive polymer nanocomposites have great potential in the fields of electromagnetic interference(EMI)shielding,sensors,energy and display.Ag NWs and MXene have attracted much attention as conductive fillers because of their excellent electrical conductivity and rich surface groups.At present,there are many intrinsic problems such as aggregation and stacking in the composite process of conductive nanomaterials and polymers,which greatly affect the comprehensive properties of polymer nanocomposites.In this paper,according to the properties of Ag NWs,MXene and polymer,the surface structure of Ag NWs and MXene nanomaterials was functionalized.Combined with traditional freeze-drying technology and self-assembly strategy,the relationship between composition,structure and properties of Ag NWs and MXene polymer nanocomposites was studied systematically.The Ag NWs/ANF film and MXene-based silicone foam were prepared.The main contents and innovative achievements of this paper are as follows:(1)Preparation and properties of Ag NWs/ANF films with high conductivity and thermal insulation.The processing and preparation technology of high performance aramid nanofiber(ANF)treated with alkali solution was developed.The N-H groups of ANF was changed by this technology,and the residual polyvinylpyrrolidone on the surface of Ag NWs was used to form hydrogen bond to enhance the interfacial compatibility between Ag NWs/ANF.While ensuring the excellent mechanical properties of the Ag NWs/ANF film,the electrical conductivity of Ag NWs/ANF film was improved.The experimental results show that when the loading of Ag NWs is 40 wt%,the conductivity of Ag NWs/ANF film is the best,which can reach 652 S cm^-1 and the electromagnetic shielding property can reach 70.8 d B.(2)Preparation and properties of high hydrophobicity and silicone modified MXene-based electromagnetic shielding foam.The stable three-dimensional network structure of MXene was constructed by bonding a small amount of hydroxyethyl cellulose adhesive.MXene-based mixed aerogels are modified by silicone resin to solve the problems of poor mechanical properties of MXene-based mixed aerogels.The experimental results show that the water contact angle of MXene-based silicon foam is above 150°.When the volume fraction of MXene is 0.69 vol%,the electrical conductivity of MXene-based silicon foam can reach 3166.4 S m^-1 and the electromagnetic shielding property can reach 74 d B.